Free Experiment On The Synthesis And Reaction Of Ferrate Report Example

Introduction

Disposal of pharmaceutical products into the water bodies poses a serious threat to the existence of aquatic life. For instance, synthetic endocrine-disrupting chemicals (EDCs) 17α-ethinyl estriradiol have a significant effect on the physiology of aquatic organisms (Rohde, 264). Consequently, there is the need to devise environment-friendly and efficient means of removing such pollutants from the ecosystem. Diatrizoic acid (DTZA) is one of the most widely used pharmaceutical products in our daily life. It is an x-ray contrast media compound commonly used in the imaging of soft tissues. Ferrate is a suitable disinfectant for removing these pollutants from water. It does so by oxidizing them given that it has a high oxidizing power (+6 oxidizing state).
This experiment had four aims. First, it sought to study the laboratory preparation of ferrate using wet chemical method. Secondly, the experiment sought to determine whether ferrate reacts fast with DTZA or not. The experiment also sought to determine the percentage yield of ferrate through the wet chemical method used. The last aim of the experiment was to determine how changes of the concentration of DTZA affect the rate of reaction between DTZA and ferrate.

Four research questions were drafted:

How is ferrate synthesized in the laboratory using wet chemical method?
This research question led to the formulation of the first aim of the experiment.
What is the percent yield of the wet chemical method used to synthesize ferrate?
This research question led to the drafting of the third aim of the experiment which sought to determine the percent yield of the reaction involved in synthesizing ferrate. This question also helped guide the experiment to determine whether it was accurate or not.

What is the rate of the reaction between ferrate and DTZA?

This research question helped in formulating the second aim of the experiment. It helped ensure that the experiment is focused towards achieving that aim.

Do the changes in the concentration of DTZA affect the rate of its reaction with ferrate?

This research question led to the formulation of the forth aim of the experiment. It also helped guide the experiment in achieving this aim.

The below hypothesis was formulated for this experiment:

The higher the concentration of DTZA is, the higher the rate of the reaction between DTZA and ferrate becomes, and vice versa.
There were four five used in the experiment. The independent variables were ‘time’ and ‘concentration of DTZA’. On the other hand, the dependent variable was ‘absorbance’ while the control variables were ‘temperature’ and ‘pressure’. The control variables were controlled by ensuring that all the reactions were performed at the same temperature and pressure conditions.
The only change made to the handout is that the reactions between ferrate and DTZA were performed with different concentrations of DTZA.

Results

The results of part 1 of the experiment are as shown in table 1 below:

Discussion

In part 1, it was observed that the beaker became warm when NaOH pellets were added. This rise in the temperature of the solution in the beaker indicates that the reaction was exothermic. Furthermore, as the reaction progressed, the solution in the beaker turned purple. The purple color indicated that ferrate (FeO42) had been formed. During the reaction between ferrate and DTZA, the purple color disappeared gradually until the solution in the beaker became yellow-brownish. The yellow-brownish color was due to the presence of Fe+3 formed as a product of the reaction between ferrate and DTZA.
In trial 1 of the reaction of ferrate with 0.04M DTZA, the absolute initial rate was found to be 7.84E-07M/s. On the other hand, the initial rate for trial 2 of the same reaction was found to be 8.028E-07M/s. Therefore, the average absolute value of the rate of the reaction between ferrate and 0.04M DTZA was found to be 7.934E-07M/s. In the reaction between ferrate and 0.1M DTZA, the absolute values of the initial rates of the reaction were found to be 4.86E-07-07M/s and 4.64E-07M/s in the first and second trials respectively. The average initial rate of reaction was found to be 4.75M/s. Comparing the initial rates of the two reactions shows that the reaction between ferrate and 0.04M DTZA took place faster than that between ferrate and 0.1M DTZA. Besides, the gradients of the graphs of absorbance against time show that the reaction involving 0.04M DTZA occurred faster than that involving 0.1M DTZA. In this case, the gradient of the graph representing the reaction between ferrate and 0.04M DTZA shown in figure 4 is 4.90E-07 while that of the graph representing the reaction between ferrate and 0.04M DTZA is 4.86E-07. Since the gradients of these graphs indicate the average rates of the reactions they represent, it turns out that the reaction involving 0.04M DTZA with ferrate occurred faster than the one involving 0.1M DTZA with ferrate. Consequently, this experiment finds that the higher the concentration of DTZA is, the lower the rate of reaction becomes and vice versa. Therefore, the hypothesis is rejected. The experiment also found that the rate of the reaction between ferrate and DTZA is high.
One of the limitations of this experiment was that the brown color formed during the reaction between ferrate and DTZA reflected the purple color of the ferrate as the reaction progressed. This might have led to higher readings of absorbance values by the spectrophotometer. It can be alleviated by adding a substance that only reacts with Fe3+ to form a colorless solution.

Conclusion

This experiment was successful since the students gained many insights into the preparation and the reaction of ferrate. All the aims of the experiment were also achieved.

Works Cited

Rohde, Klaus. The Balance of Nature and Human Impact. , 2013. Print.